A piston of this kind is known from WO 2007/036357 A1, which is incorporated by reference. Here, the piston is provided in a disc brake in such a way that it can be moved electromechanically and hydraulically. In the case of electromechanical actuation, a drive spindle is made to rotate by an electric motor via a gear mechanism. In the process, a thread on the spindle interacts with a drive nut which is provided in a rotationally fixed manner, causing the latter to be moved axially. The drive nut comes to rest against a conical surface in the piston and thus transmits the movement to the piston and the brake pad. The conical surface is arranged at the transition between the piston head and the wall, resulting in a thickened portion in this region which leads to a relatively high weight and makes the piston difficult to produce.